It is believed that noise has traditionally been a problem in most fuel delivery systems. In such systems, each moving component has the potential to create or propagate noise. Examples of such fuel system components include fuel injectors, pressure regulators, fuel pumps, and check valves. Additionally, it is believed that mechanical vibration that is imparted to a fuel system can generate noise at its own signature frequency.
One type of known pressure pulsation damper includes a spring and a diaphragm. However, this type of damper suffers from a number of deficiencies. For example, it is believed that this type of damper is effective only for lower frequency pressure pulsations, i.e., in a range of 20-100 Hertz. Such lower frequency pulsations can be caused by the operation of fuel injectors. The effective damping range for a spring and diaphragm type pressure pulsation damper is believed to be achieved as a result of a relatively high degree of flexibility or pliability. However, this same flexibility or pliability causes spring and diaphragm type pressure pulsation dampers to be ineffective for damping higher frequency pulsations. Applicant has recognized that a more rigid structure is required for damping such higher frequency pulsations.
It is believed that for fuel systems there is a need to damp pressure pulsations and attenuate noise transmission in a higher frequency range, e.g., 200-500 Hertz. This higher frequency range is believed to be well above the operating range of spring and diaphragm type pressure pulsation dampers.